A distributed telecommunications network can have multiple components. At a primary or main server, a gatekeeper is responsible for address translation (e.g., translation of H.323 identifiers and E.164 numbers to endpoint IP addresses), call admission control (which controls endpoint admission into the H.323 network), bandwidth control (which manages endpoint bandwidth requirements), and zone management (which involves primarily controlling the endpoint registration process). In a typical distributed network, media gateways positioned in remotely located network regions provide resources (e.g., Digital Signal Processor (“DSP”) and trunking resources) to local endpoints. To permit the gatekeeper associated with the primary or main server to maintain control, remotely located gateways and endpoints register with the gatekeeper. A heart beat or keep alive mechanism permits each of the remotely located components to monitor the state of the primary or main server and the connection between the server and the remote component. To provide redundancy, one or more remote network segments are serviced by a remotely located survivable gatekeeper/server. The survivable gatekeeper remains inactive until the primary server and/or connection to it malfunctions or is otherwise not available. In response to an attempted registration by a gateway, the survivable gatekeeper becomes active and attempts to notify the primary server of its changed status.
When a malfunction occurs followed by a recovery, a split registration can result. A split registration refers to a state where some remotely located endpoints are associated with a local gateway, and registered with a survivable gatekeeper, while other remotely located endpoints from the same network region are registered with the gatekeeper in the primary server. Split registration is possible when the duration of the malfunction is longer than the transition point of the gateways but shorter than the transition point of all or some of the endpoints. The transition point refers to the time interval during which the respective component is required to attempt registration only with the primary or main server. After the transition point, the component is free to attempt registration with the respective survivable processor.
During split registration, the endpoints registered with the gatekeeper in the primary or main server do not have access to trunk or gateway resources and would therefore be unable to make calls or contact some other endpoints in the enterprise network. For calls that can be made, the remote endpoints registered with the primary gatekeeper will consume precious bandwidth over the wide area network positioned between the network region and the primary server because the resources needed for the call are located at the primary server 104. This problem can occur even when the primary server 104 has some trunk resources in other regions. As an illustrative example, the endpoints registered with the primary server 104 are unable to use the primary server's trunk resources because location-based routing rules prevent access to these trunk resources.
Recovery from split registration is commonly manual and can take many hours for large systems.
There have been attempts, though of varying degrees of success, to address split registration. In one approach, when a station is registered on a survivable gatekeeper and an inbound call arrives at the primary server for that station, the call is redirected through the Public Switched Telephone Network (“PSTN”) to the survivable gatekeeper. This approach applied only to inbound, and not outbound, calls. In another approach, when a station is registered on a survivable gatekeeper and a station-to-station call within the enterprise network arrives at the primary server for that station, the call is redirected through the PSTN to the survivable gatekeeper. This approach is only for station-to-station calls and not for inbound or outbound calls.
There is a need for a method and system to prevent or reduce the likelihood or extent of split registration.